i tried to swap over a cloth seat cover for a leather one severasl months ago when i was swapping my cloth trim for leather,
i found it very difficult to remove the covers, just removing the leather headrest cover was a real struggle as you have to get the angle just right to release the securing clip
as for the seat cover, i managed to remove the back plate and various bits, but could not pull the cover off, it was like it was stiched to the padding of the seat.
as it stands i currently have drivers seat in cloth and the rest of the interior in leather
i will try and tackle this again when i return to the uk in several weeks, but fear that i will have to take it to cass brothers in bromley when i have some spare cash
i was told when i bought the leather it was a straight forward process to remove the seat covers, i sure didnt find it that way
good luck with yours